One time my wife and I had a random conversation, utterly random, about cat hamster wheels. Like, why doesn't that exist? I got an ad for it the next day (it exists). I don't believe that my phone is not listening to me and I challenge you to choose a random word out of the dictionary and say it 100 times in front of your phone.
Your wife probably googled them as soon as you were done talking about them and then you using the same network got an ad for them.